The ketene-surrogate coupling: catalytic conversion of aryl iodides into aryl ketenes through ynol ethers.

Lewis acid-promoted [2 + 2] cycloadditions of alkenes with aryl ketenes.

A method for the [2 + 2] cycloaddition of aryl ketenes and alkenes is presented. The process involves the in situ generation of a ketene in the presence of a Lewis acid. The utility of products is demonstrated towards the synthesis of a common scaffold found in several natural product families.

Carbogallation of alkynes using gallium tribromide and silyl ketene acetals and synthetic application to cross-coupling with aryl iodides.

Nucleophilicity toward ketenes: rate constants for addition of amines to aryl ketenes in acetonitrile solution.

Second-order rate constants (k(Nu)) have been measured for the addition of amines to ketenes 4-6 in acetonitrile solution by the laser flash photolysis technique. These ketenes are formed from a photochemical Wolff rearrangement of diazoketones 1-3, respectively. For all diazoketones studied, the presence of amines as nucleophiles in the reaction medium results in the formation of an intermedia...

Enantioselective Nucleophile-Catalyzed Synthesis of Tertiary Alkyl Fluorides via the α-Fluorination of Ketenes: Synthetic and Mechanistic Studies

The catalytic asymmetric synthesis of alkyl fluorides, particularly α-fluorocarbonyl compounds, has been the focus of substantial effort in recent years. While significant progress has been described in the formation of enantioenriched secondary alkyl fluorides, advances in the generation of tertiary alkyl fluorides have been more limited. Here, we describe a method for the catalytic asymmetric...

Copper-catalyzed coupling of triaryl- and trialkylindium reagents with aryl iodides and bromides through consecutive transmetalations.

An efficient copper(I)-catalyzed coupling of triaryl and trialkylindium reagents with aryl iodides and bromides is reported. The reaction proceeds at low catalyst loadings (2 mol%) and generally only requires 0.33 equivalents of the triorganoindium reagent with respect to the aryl halide as all three organic nucleophilic moieties of the reagent are transferred to the products through consecutiv...